What's new:
-----------

- New API: secure_getenv.


What changed:
-------------


Bug Fixes
---------

- Relax fork child permissions to avoid a potential fork failure.
  Addresses: https://cygwin.com/ml/cygwin/2019-02/msg00234.html

- Fix Command-line argument handling of kill(1) in terms of negative PID.
  Addresses: report on IRC

- Fix an accidentally introduced O_TEXT handling of pipes inherited
  from native Windows processes.
  Addresses: https://cygwin.com/ml/cygwin/2019-02/msg00246.html

- Re-enable creating user token from scratch in seteuid to allow
  user context switch on old systems not supporting MsV1_0S4ULogon.
  Addresses: https://cygwin.com/ml/cygwin/2019-02/msg00277.html
